The Coroner is an independent official with responsibility under the law for the medico-legal investigation of certain deaths occurring in San Mateo County.

The Coroner's office must inquire into the circumstances of sudden, unexplained, violent, and unnatural deaths.  This may require a post-mortem examination sometimes followed by an inquest.  The Coroner's inquiry is concerned with establishing whether or not death was due to natural or unnatural causes.  If a death is due to unnatural causes, for example in a road traffic accident, accident at work, or by drowning, then an inquiry must be completed by law.